Hi Terry, Really appreciate all your posts.
It is the original feedhorn, as the dish has a round plastic holder it fits into. i held the std lnb and tried moving in and out, the best result was flush where the original feedhorn should be, so the focal point must be correct. I have tried adjusting the arms and i am pretty sure i have it at the optimum point.
Today i drilled three holes through the plastic feedhorn holder at 120 degree spacing and used three screws and bolts to hold the Invacom Quad lnb in place, it work quite well. I have 50% signal & 50% quality in the fog on 10818.
Also I borrowed a great Canal Plus receiver from a friend CDC-7000. Which allows you to easily select which satellite TP you are looking at, check out:
_http://www.canaldigital.no/TV/Parabol/Temasider/Landingssider/Mottakere/Canal-Digital-CDC-7000/
This really helped, because unlike my Pace , this gives you the reading even if not locked and you can see it fluctuating up and down in 1% variations. Blinding!
I am now going to get hold of a C120 MTI AP8 and try that with the feedhorn again, I am also considering buying a IDLB-SINL40-ULTRA-OPP or the twin.